Water Droplets May Be Able To Charge Smartphones

You learned in eighth grade science class that water conducts electricity, but you know not to put your smartphone in water and risk smartphone death. That idea is being flipped on its head as researchers at the Massachusetts Institute of Technology (MIT) are making the connection between batteries and water as a conductor of electricity.

In a press release, MIT explained its findings: “Last year, MIT researchers discovered that when water droplets spontaneously jump away from superhydrophobic surfaces during condensation, they can gain electric charge in the process. Now, the same team has demonstrated that this process can generate small amounts of electricity that might be used to power electronic devices.”

A “superhydrophobic surface” is a surface that repels water, usually involving silica-based nano-coatings. According to MIT, this new research means phones could be charged by the humidity in the air. The research could also pave the way for a new system of producing clean water and generating power.

“The same process can be used to generate power, simply by giving the second plate a hydrophilic surface,” MIT reported. “As the droplets jump, they carry charge from one plate to the other; if the two plates are connected through an external circuit, that charge difference can be harnessed to provide power.”

If water droplets jumping between superhydrophboic and hydrophilic plates create an electric charge, then the day is coming when we could potentially charge our smartphones using water in the air. Scientists have already managed to create waterproof phones using nano-coatings, so why can’t they use nano-coated, superhydrophobic plates to charge our phones with water?

MIT’s post-doctoral fellow Nenad Milijkovic said all we need to do is create a relationship between water in the air and a source of power or energy.

“Water will condense out from the atmosphere, it happens naturally,” Milijkovic told MIT. “The atmosphere is a huge source of power, and all you need is a temperature difference between the air and the device.”